The present invention relates to changing the shape of a universal substrate, and more particularly to the improvement of a substrate suited to bonding a liquid phase material in a specific pattern.
Substrates called universal substrates have been around for some time. These substrates had spotted copper film regions to which solder adhered well, with these regions laid out in a regular pattern. It was possible with these universal substrates to solder or otherwise fix parts in any desired position on the substrate. The various parts were connected to other parts via lead wires, or were wired to each other by solder continuously applied by soldering iron in the copper film region.
A certain amount of a fluid must be uniformly bonded over the entire pattern formation region in order to form a thin film in the shape of a pattern having a specific surface area. The above-Mentioned universal substrates, however, were not well suited to such applications.
Accordingly, to bond this specific amount of fluid to a pattern formation region of a specific surface area, it was, of course, necessary to form a bank (dividing member) along the outer periphery of the pattern formation region so that the fluid would not run out of the pattern formation region, and to keep the fluid from running out of the pattern region until it solidified.
A thin film formation method that involved the formation of a bank, however, had numerous drawbacks; namely, the trouble it took to form the bank, the excessive bumpiness of the substrate surface resulting from the bank, and the necessity to select a bank material that would work with both the substrate surface and the fluid.
An ink-jet system which discharges ink jets can be adopted here when the pattern is being formed with a fluid.
The resolution with an ink-jet system is fine at 400 dpi, for example, and it is thought that if a fluid which can be used in industrial applications can be discharged from individual nozzles then it will be possible to form optional patterns with a width of the xcexcm order. That is to say, with the ink-jet system it is possible to form a pattern if the ink is changed for some other industrial fluid, without the need for facilities such as a factory, and so the ink-jet system is very desirable for use in industrial applications.
However, although useful for forming fine patterns, when such ink-jet systems are used industrially considerable spreading of the liquid droplets of fluid discharged cannot be avoided and, when forming a fine pattern such as those used in the universal substrate type semiconductor process in particular, the formation or a bank along the outer perimeter of the pattern forming region is not achieved to perfection.
In order to solve the above problems, the inventors conceived a method for forming a specific pattern with which it is possible to cause a certain amount of fluid to adhere uniformly without the use of a dividing member or the like within a pattern region of a specific shape.
A first object of the present invention is to provide a substrate to which a suitable amount of fluid will adhere in a pattern formation region of a specific surface area.
A second object of the present invention is to provide a method for manufacturing a substrate to which a suitable amount of fluid will adhere in a pattern formation region of a specific surface area.
An invention that achieves the first object is a substrate for forming a patterned thin film by causing a specific fluid to adhere, comprising a pattern formation region patterned in a specific shape for forming the film. This substrate for forming a specific pattern is characterized in that the pattern formation region is constituted by the disposition according to specific rules of an affinity region having an affinity to the fluid within a non-affinity region not having an affinity to the fluid. For example, this substrate is constituted by the disposition of the pattern formation region by a plurality of specific rules. Alternatively, the pattern formation region is formed in a specific graphic shape.
The xe2x80x9cfluidxe2x80x9d here is not only an ink, but any medium whose viscosity allows it to be discharged from a nozzle and which can be used in industrial applications. This fluid may be water-based or oil-based. It may also be a colloidal mixture. xe2x80x9cHaving an affinityxe2x80x9d means that the contact angle with respect to the fluid is relatively small, while xe2x80x9cnot having an affinityxe2x80x9d means that the contact angle with respect to the fluid is relatively large. These two expressions are used in contrast to each other for the sake of convenience in order to illustrate the behavior of the film with respect to the fluid. The above-mentioned xe2x80x9caffinity regionxe2x80x9d or xe2x80x9cnon-affinity regionxe2x80x9d can be laid out in a spotted pattern, a mosaic pattern, a striped pattern, or any another pattern. The shape of the individual regions may be circular, triangular, rectangular or another such polyhedral shape, or linear. There are no restrictions on the size of the individual regions.
An invention that achieves the second object is a method for manufacturing a substrate for forming a patterned film by causing a specific fluid to adhere, comprising the steps of:
a) forming a paraffin layer by applying a paraffin coating to a base, and
b) removing the paraffin layer from an affinity region having an affinity to the fluid by supplying energy along this affinity region such that the affinity region is disposed according to specific rules within a non-affinity region not having an affinity to the fluid in a pattern formation region in which the patterned film is formed.
Another invention that achieves the second object is a method for manufacturing a substrate for forming a patterned film by causing a specific fluid to adhere, comprising the steps of:
a) forming a metal layer from a specific metal on a base,
b) removing the metal layer by supplying energy to the region other than the pattern formation region in which the patterned film is formed,
c) removing the metal layer from a non-affinity region not having an affinity to the fluid by supplying energy along this non-affinity region such that an affinity region having an affinity to the fluid is disposed according to specific rules within the non-affinity region in the pattern formation region, and
d) immersing the base from which the metal has been selectively removed in a mixed liquid containing a sulfur compound.
The above-mentioned sulfur compound preferably has the opposite property from that of the base surface in regard to affinity to the fluid.
Another invention that achieves the second object is a method for manufacturing a substrate for forming a patterned film by causing a specific fluid to adhere, comprising the steps or:
a) masking a base with a mesh mask that covers the region other than a pattern formation region in which the patterned thin film is formed and also covers a non-affinity region not having an affinity to the fluid such that an affinity region having an affinity to the fluid is disposed according to specific rules within the non-affinity region in the pattern formation region,
b) plasma-working the base covered with the mesh mask, and
c) performing a modification treatment on the molecules dissociated by the plasma working.
Yet another invention that achieves the second object is a method for manufacturing a substrate for forming a patterned film by causing a specific fluid to adhere, comprising the steps of:
a) masking a base with a mesh mask that covers the region other than a pattern formation region in which the patterned thin film is formed and also covers a non-affinity region not having an affinity to the fluid such that an affinity region having an affinity to the fluid is disposed according to specific rules within the non-affinity region in the pattern formation region, and
b) performing a modification treatment on the mesh-masked base by irradiating it with ultraviolet rays.
Another invention that achieves the second object is a method for manufacturing a substrate for forming a patterned film by causing a specific fluid to adhere, comprising the steps of:
a) forming a thin film from a material having an affinity to the fluid on a base furnished with a surface not having an affinity to the fluid,
b) providing a photoresist that covers an affinity region having an affinity to the fluid such that the affinity region is disposed according to specific rules within a non-affinity region not having an affinity to the fluid in a pattern formation region in which the patterned film is formed, and
c) etching the base on which the photoresist has been formed and etching the region other than the region where the photoresist is provided.
Still another invention that achieves the second object is a method for manufacturing a substrate for forming a patterned film by causing a specific fluid to adhere, comprising the steps of:
a) applying a charge to the entire surface of a base,
b) dissipating the charge by applying energy to the region other than a pattern formation region in which the patterned thin film is formed,
c) dissipating the charge of a non-affinity region not having an affinity to the fluid such that an affinity region having an affinity to the fluid is disposed according to specific rules within the non-affinity region in the pattern formation region, and
d) bonding a specific substance to the affinity region where the charge was not dissipated.
Still another invention that achieves the second object is a method for manufacturing a substrate for forming a patterned film by causing a specific fluid to adhere, comprising the step of:
forming an affinity film in an affinity region having an affinity to the fluid such that the affinity region is disposed according to specific rules within a non-affinity region not having an affinity to the fluid in a pattern formation region in which the patterned thin film is formed.
It is preferable here to employ an ink jet method to form the patterned film from a fluid on the substrate. First, the fluid that serves as the material for the film is supplied to a cavity designed so that it can be filled with a fluid from an ink jet recording head. Voltage is then applied to a piezoelectric element designed such that a volumetric change can be effected in the cavity, and droplets of fluid are discharged from a nozzle so that the fluid will adhere evenly over the entire surface of the pattern formation region.